<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <canvas id="canvas"></canvas>
    <!-- <script>
        let canvas = document.getElementById('canvas');
        canvas.width = 300 * devicePixelRatio;
        canvas.height = 300 * devicePixelRatio;
        canvas.style.width = '300px';
        canvas.style.height = '300px';
        canvas.style.border = '1px solid red';
        const ctx = canvas.getContext('2d');

        ctx.save();

        ctx.scale(devicePixelRatio, devicePixelRatio);
        ctx.translate(150, 150);
        ctx.rotate(Math.PI);
        
        ctx.fillStyle = 'red'
        ctx.restore();
        ctx.fillRect(0, 0, 150, 150);
    </script> -->
</body>
</html>